Mr. Bubble's Notice of a Whin Dyke. IS 



although it has been found in the workings of Byker, Lawson's Main, 

 and Walker Colliery. 



I, therefore, assume, that it is not the character of this Dyke to shew 

 itself frequently at the surface, but that it undulates in a vertically ser- 

 pentine direction {see diagram, Plate IV.), the more elevated parts only, 

 as at Coley Hill, Ouseburn, and Simonside, appearing at the surface. 

 The more depressed parts descending to various depths, in different 

 places, as will presently be shewn. 



Under this view of its character, the non-appearance of the Dyke be- 

 tween Coley Hill and the points where it has been proved in Montague 

 Main Colliery, and in Benwell, is the less extraordinary ; and, it may 

 be remarked, that that part of the country, in which no traces of it have 

 been discovered, either on the surface or in the underground workings, 

 is on the dip side of the Main Dyke, which depresses the stratification 

 90 fathoms below the level of the Beaumont Seam, in Montague Main 

 and Benwell Collieries, where the Whin Dyke occurs. 



Neither the Beaumont Seam nor the Low Main have yet been worked 

 on the dip side of the Main Dyke, in the line of the Whin Dyke ; we do 

 not, therefore, know at present whether it intersects those seams or not 

 in that part. 



From the point in the Benwell woi'kings, where we have crossed this 

 Dyke, it runs in a South East direction into the Town Moor, through 

 which, we have a traditionary account that a " Cinder Dyke" runs, 

 which spoils the Coal in the High Main Seam for upwards of 100 

 yards in breadth, through the whole extent of the Moor, from near the 

 Cow-gate to the Bull-park, on the East side of the Moor, where the 

 Main Coal is not supposed to be more than 20 fathoms from the surface. 

 The High Main Seam, it is to be remarked, lies about Q5 fathoms above 

 the Low Main, and 95 above the Beaumont Seam. 



A pit, recently sunk and bored by Mr. Burdon Sanderson, at his Coal 

 staith, near the North end of Brandling Place, to the High Main Seam, 

 is in a nip of the Coal, which I consider to be occasioned by the Whin 

 Dyke, and that this pit is sunk on the North side of it. 



The next point, at which we discover any appearance of the Dyke, is 



